On Sat, 2012-01-14 at 12:51 +0000, Bart Van Assche wrote: > + * cmd_sg_entries, a number in the range 1..255 that specifies > + the maximum number of direct data buffer descriptors in an
s/direct/indirect/ > + SRP_CMD. Direct data buffer descriptors are communicated via > + the SRP_CMD header. With allow_ext_sg=0 the parameter So are indirect buffer descriptors, which is actually what this parameter controls. > + cmd_sg_entries defines the maximum S/G list length for a > + single SRP_CMD. Also, commands whose S/G list length exceeds s/. Also,/ and/ > + this limit after S/G list collapsing will fail. > + * allow_ext_sg, whether ib_srp is allowed to use indirect data > + buffer descriptors when communicating with an SRP target. allow_ext_sg, if true, the initiator is allowed to use more indirect data buffer descriptors than will fit in the SRP_CMD, allowing for larger requests to be handled. If false (the default), the length of the S/G list after merging is limited to cmd_sg_entries. Target support for retrieving the indirect descriptor table via RDMA is required to set this to true. > + * sg_tablesize, a number in the range 1..2048 specifying the > + maximum S/G list length the SCSI layer is allowed to pass to > + ib_srp. Specifying a value that exceeds cmd_sg_entries is > + only safe with indirect data buffer support enabled > + (allow_ext_sg=1). s/only safe/only completely safe/ If this value exceeds cmd_sg_entries and a failure occurs while collapsing the list into fewer S/G entries, the command will fail. This failure case only appears to be possible on IBM HCAs. > +What: /sys/class/scsi_host/host<n>/allow_ext_sg > +Date: May 19, 2011 > +KernelVersion: 2.6.39 > +Contact: [email protected] > +Description: Whether ib_srp is allowed to use indirect data buffer > + descriptors when communicating with an SRP target. Whether the initiator is allowed to use more S/G entries than will fit in the command request when communicating with an SRP target. > +What: /sys/class/scsi_host/host<n>/cmd_sg_entries > +Date: May 19, 2011 > +KernelVersion: 2.6.39 > +Contact: [email protected] > +Description: Maximum number of direct data buffer descriptors to send to > + the target in a single SRP_CMD. s/direct/indirect/ > +What: /sys/class/scsi_host/host<n>/failed_reconnects >+What: /sys/class/scsi_host/host<n>/reconnect_tmo These attributes does not exist at this point in the patch series. Perhaps this patch should be the last one in the series? -- Dave Dillow National Center for Computational Science Oak Ridge National Laboratory (865) 241-6602 office -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
